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UHF System Configuration
Antenna installation position
Distance between transmitter and antenna
Line-of-sight service area ranges for different RF power levels are listed below.
If the transmitter is located too close to the antenna, input overload may occur, leading to intermodulation
distortion and noise. A distance of at least 2 to 3 meters between transmitter and antennas should always
be maintained.
If the transmitter and antenna are too far apart, the service area will become doughnut-shaped.
Installation should allow direct line of sight from transmitter to antenna
There should be no obstacles between the transmitter and antennas.
Normally, the antennas should be mounted at a height above average human height, looking up from the
transmitter at an inclined angle.
Keep away from windows
If wireless systems are operated on several floors of a building, antennas near windows may cause
interference between floors.
For installation in high-rise buildings, antennas should be positioned at least 3 meters away from windows.
On higher floors, radio signals from other microphones may interfere with reception even over considerable
distances.
Keep a clearance of several tens of centimeters from the ceiling
Close proximity to the ceiling can cause reflections that negatively affect reception sensitivity. When
installing antennas in corners, also keep a clearance of several tens of centimeters from adjacent walls.
Locations to avoid
Do not install antennas in the following types of locations. Otherwise signal reception may suffer or noise
may occur.
Behind ceiling or wall finishing layers
Near windows, metal frames/plates, or electric appliances (lighting fixtures, motors, elevators, power
distribution panels, etc.)
Near electronic equipment (computers, dimmers, TV sets, video cameras, etc.)
Install antennas with correct orientation
The sensitivity pattern of an antenna extends in the horizontal direction from the correct mounting
orientation. For example, if the AN-820A is mounted to the ceiling pointing down, reception sensitivity may
decrease.
RF power
Transmission distance
10 mW
60 m (196.9 ft.)
1 mW
20 m (65.6 ft.)
Booste
Configuring a DWX System